One of the most sensitive and variable mechanisms in biological systems is that of conformational transitions. The biological functions of both proteins and nucleic acids are frequently under conformational control. Studies will be conducted on both biological materials and synthetic models of these biological macromolecules. Research will be directed towards methods of determining and predicting the conformation and conformational transitions in protein models (poly-alpha-amino acids) and nucleic acids (model polynucleotides). Physical-chemical techniques such as optical rotatory dispersion, circular dichroism, tritium exchange, and fluorescence will be exploited. Research will be directed towards elucidating the conformational consequences and biological significance of the interaction of DNA with proteins, such as the histones and non-histone proteins found in the nucleus. Model systems, utilizing model polypeptides and polynucleotides, will be studied to investigate the inter-dependence of the conformation of both components of these models. Such studies will perhaps lead to the understanding of how nucleoproteins are involved in control of genetic expression, and how failures in control mechanisms operate.